Notepad

Abstract

To provide a writing instrument capable of more accurately controlling the amount of coating liquid supplied to a pen tip while preventing leakage of the coating liquid.SOLUTION: The writing instrument includes: a pen tip portion for applying coating liquid; a coating liquid storage portion for storing the coating liquid; a tubular portion formed in a tubular shape so as to cover the coating liquid storage portion and fixed to the pen tip portion; a valve mechanism provided at a tip portion of the coating liquid storage portion; an operation member fixed to the pen tip portion, and capable of opening the valve mechanism and allowing the coating liquid that has flowed out of the coating liquid storage portion to flow through the valve mechanism to the pen tip side; a tubular elastic member capable of expanding and contracting in an axial direction, connecting the valve mechanism and the operation member, and defining a flow path for the coating liquid between the valve mechanism and the operation member. The coating liquid storage portion is axially movable relative to the pen tip portion. The operation member opens the valve mechanism as the coating liquid storage portion moves relative to the pen tip portion.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a writing instrument. [Background technology]

[0002] 2. Description of the Related Art Water brushes, which are filled with water, are known as writing implements. Water brushes are used when practicing calligraphy or when painting pictures with water-based paints outdoors.

[0003] For example, Patent Document 1 describes a water brush that includes a brush tip for applying water and a shaft extending from the brush tip, the shaft having a coating liquid storage section for storing water. In this water brush, the coating liquid storage section has a water passage hole provided at the tip and a valve mechanism provided at the rear end, and further includes an operating section for switching the valve mechanism between open and closed states. That is, according to this water brush, the user presses the operating section to open the valve mechanism, which connects the coating liquid storage section to the external environment, allowing water to flow out of the water passage hole and supply water to the brush tip. In this way, in this type of writing instrument, it is required to supply an appropriate amount of water to the brush tip at the timing intended by the user, and this is not limited to water, but also applies to writing instruments equipped with ink. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-209531 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the writing instrument described in Patent Document 1, the brush tip and the coating liquid storage section are always in communication with each other through a water hole, so it is difficult to appropriately control the supply amount of coating liquid such as water or ink by only operating the operating section. In particular, when the viscosity or surface tension of the coating liquid is low, there is a risk that the coating liquid will flow out from the water hole even when the valve mechanism is closed, making it difficult to accurately control the supply amount of coating liquid to the brush tip.

[0006] In addition, when supplying the coating liquid to the brush tip, it is necessary to prevent the coating liquid from leaking from places other than the brush tip. In the water brush of Patent Document 1, the valve mechanism and the operating part for opening the valve mechanism are located at the rear end, so no measures are taken to prevent the coating liquid from leaking from these places.

[0007] In view of the above circumstances, an object of the present invention is to provide a writing instrument that is capable of more accurately controlling the amount of coating liquid supplied to the pen tip while preventing leakage of the coating liquid. [Means for solving the problem]

[0008] A writing instrument according to an embodiment of the present invention comprises: A pen tip portion for applying the coating liquid; a coating liquid storage section for storing a coating liquid; a cylindrical portion formed in a cylindrical shape so as to cover the coating liquid storage portion and fixed to the pen tip portion; a valve mechanism provided at a tip of the coating liquid storage section; and an operating member fixed to the pen tip portion, the operating member being capable of opening the valve mechanism and allowing the coating liquid flowing out of the coating liquid reservoir portion to flow toward the pen tip side via the valve mechanism; a cylindrical elastic member that is expandable and contractable in an axial direction, the cylindrical elastic member connecting the valve mechanism and the operating member and defining a flow path for the coating liquid between the valve mechanism and the operating member; Equipped with the application liquid storage section is movable in an axial direction relative to the pen tip section, The operating member opens the valve mechanism in response to relative movement of the application fluid reservoir with respect to the pen tip portion.

[0009] According to the writing implement having such a configuration, since it is provided with a cylindrical elastic member that connects the valve mechanism and the operating member, it is possible to prevent the coating liquid from leaking from between them. In addition, the coating liquid storage section is movable relative to the pen tip section in the axial direction, and the operating member opens the valve mechanism in accordance with the relative movement of the coating liquid storage section, thereby discharging the coating liquid from the coating liquid storage section through the flow path of the valve mechanism and the cylindrical elastic member, while supplying the coating liquid to the pen tip section. Furthermore, when the valve mechanism is closed, the tip of the coating liquid storage section is blocked by the valve mechanism, so that the coating liquid is prevented from accidentally flowing out from the tip to the pen tip side. Therefore, according to the above configuration, the user can relatively accurately control the amount of coating liquid supplied to the pen tip section by opening and closing the valve mechanism by moving the coating liquid storage section relative to the pen tip section.

[0010] In addition, in the writing instrument, preferably, The operating member presses the valve mechanism to open the valve mechanism.

[0011] According to a writing instrument having such a configuration, the operating member presses the valve mechanism to open the valve mechanism, and therefore the structure is relatively simple.

[0012] In addition, in the writing instrument, preferably, One end of the cylindrical elastic member covers the valve mechanism and the tip of the coating liquid reservoir.

[0013] With a writing instrument having such a configuration, one end of the cylindrical elastic member covers the valve mechanism and the tip of the coating liquid storage portion, thereby preventing leakage of coating liquid from a gap that may occur between the valve mechanism and the coating liquid storage portion. Effect of the Invention

[0014] As described above, according to the present invention, a writing instrument can be provided that is capable of more accurately controlling the amount of coating liquid supplied to the pen tip while preventing leakage of the coating liquid. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 shows a schematic diagram of the internal structure of a writing instrument according to one embodiment. [Diagram 2] FIG. 2 is an exploded view of the writing instrument of FIG. [Diagram 3] FIG. 3 shows the internal structure of the valve mechanism of the writing instrument of FIG. [Figure 4] FIG. 4 is a view of the valve mechanism of the writing instrument of FIG. 1, seen from the axial rear end side. [Diagram 5] FIG. 5 is a cross-sectional view of the pressing member of the writing instrument of FIG. [Figure 6] FIG. 6 is a view of the pressing member of the writing implement of FIG. 1 as viewed from the axial rear end side. [Figure 7] FIG. 7 is a cross-sectional view of the cylindrical elastic member of the writing instrument of FIG. [Figure 8] FIG. 8 is a view of the cylindrical elastic member of the writing instrument of FIG. 1 as viewed from one side in the axial direction. [Figure 9] FIG. 9 shows the relationship between the valve mechanism, the pressing member, and the cylindrical elastic member when the valve mechanism is in a closed state. [Figure 10] FIG. 10 shows the relationship between the valve mechanism, the pressing member, and the cylindrical elastic member when the valve mechanism is in an open state. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, a writing instrument according to one embodiment of the present invention will be described with reference to the accompanying drawings.

[0017] The writing instrument 1 according to this embodiment is filled with ink as the application liquid. Furthermore, the writing instrument 1 is configured so that it can be refilled with ink when the ink is consumed.

[0018] 1 and 2, a writing instrument 1 according to this embodiment includes a pen tip section 2 for applying a coating liquid to a coating target such as paper, and a shaft section 3 extending from the pen tip section 2. The shaft section 3 includes a coating liquid storage section 31 for storing the coating liquid, and a tube section 32 formed into a cylindrical shape so as to cover the coating liquid storage section 31.

[0019] In this specification, the direction in which the writing instrument 1 extends is sometimes referred to as the axial direction, the direction perpendicular to the axial direction is sometimes referred to as the radial direction, and the direction going around the central axis of the writing instrument 1 is sometimes referred to as the circumferential direction. In addition, in the axial direction, the pen tip side is sometimes referred to as the leading end side, and the side opposite the leading end side is sometimes referred to as the trailing end side.

[0020] In this embodiment, the pen tip portion 2 has an application portion 21 that directly contacts the object to be applied and applies the application liquid to the object, a holding portion 22 that holds the application portion 21, and a cylindrical hollow portion 23 that extends from the holding portion 22 toward the rear end.

[0021] The applicator 21 is formed by a bristle bundle in which one end of a plurality of bristles is bound by adhesive. The applicator 21 has a bound portion in which one end of a plurality of bristles is bound by adhesive, and a non-bound portion in which a plurality of bristles is not bound by adhesive. The bound portion is disposed on the rear end side of the applicator 21, and the non-bound portion is disposed on the tip side of the applicator 21. In addition, a flow path extending along the axial direction is formed in the bound portion. The application liquid is supplied to the tip portion 211 of the applicator 21 through the flow path. The pen tip portion 2 having such an applicator 21 is specifically a brush tip portion 2.

[0022] Moreover, application part 21 is formed so as to taper from rear end part 212 towards tip part 211. Furthermore, rear end part 212 has enlarged diameter part 213 which is formed so as to have the largest outer diameter in application part 21.

[0023] In this embodiment, the holding part 22 is formed in a truncated cone shape tapering from the rear end side to the front end side. The holding part 22 has a through hole 221 extending along the axial direction. The through hole 221 has an inner diameter large enough to allow the non-bundled part of the application part 21 to pass through but not allow the enlarged diameter part 213 of the application part 21 to pass through.

[0024] In this embodiment, the pen tip portion 2 is fixed to the tube portion 32 in the hollow portion 23. The hollow portion 23 is formed so as to fit into the tip portion 321 of the tube portion 32 from the outside. The hollow portion 23 and the tube portion 32 are configured to be able to engage liquid-tightly. In this embodiment, a female thread is formed on the inner peripheral surface at the rear end portion 232 of the hollow portion 23, and a male thread that can be screwed into the female thread is formed on the outer peripheral surface at the tip portion 321 of the tube portion 32. This allows the hollow portion 23 and the tube portion 32 to be screwed together.

[0025] In addition, an annular sealing member 4 is provided inside the hollow portion 23. The sealing member 4 is arranged so as to be sandwiched between the rear end portion 222 of the holding portion 22 and the tip portion 321 of the tube portion 32 in a state in which the pen tip portion 2 is fixed to the tube portion 32. In addition, the sealing member 4 has an opening 41 that allows ink to pass through. The inner diameter of the opening 41 is formed to be larger than the inner diameter of the flow path of the application portion 21 and smaller than the outer diameter of the enlarged diameter portion 213 of the application portion 21. The sealing member 4 is arranged so that the opening 41 communicates with the flow path of the application portion 21. The sealing member 4 makes it easier for the ink flowing out of the application liquid storage portion 31 to be guided to the flow path in the application portion 21 through the opening 41, and thus makes it easier for the ink to be supplied to the pen tip portion 2.

[0026] The coating liquid storage section 31 is formed in a bottomed cylindrical shape having an open front end 311 and a closed rear end 312. The coating liquid storage section 31 has an internal space S for filling with ink. The coating liquid storage section 31 accommodates a spherical mixing member 314 in the internal space S, which promotes mixing of the ink. The mixing member 314 has a diameter smaller than the inner diameter of the coating liquid storage section 31, and thus moves axially in the internal space S when the writing instrument 1 is shaken in the axial direction. The mixing member 314 usually has a density greater than that of the ink. Thus, the mixing member 314 settles within the ink.

[0027] The ink may be a water-based ink or an oil-based ink.

[0028] The tube portion 32 is formed in a cylindrical shape with the front end portion 321 and the rear end portion 322 each being open. The tube portion 32 is formed so as to be able to accommodate the coating liquid storage portion 31 therein. As shown in FIG. 1, a gap G1 is formed between the inner peripheral surface of the tube portion 32 and the outer peripheral surface of the coating liquid storage portion 31, which allows the coating liquid storage portion 31 to move along the axial direction inside the tube portion 32. The coating liquid storage portion 31 may also be able to move in the axial direction relative to the pen tip portion 2. The coating liquid storage portion 31 may move inside the tube portion 32 such that a part of the inner peripheral surface of the tube portion 32 and a part of the outer peripheral surface of the coating liquid storage portion 31 are in sliding contact with each other.

[0029] Additionally, the tubular portion 32 is formed so as to expose the rear end portion 312 of the coating liquid storage portion 31. This makes it easier for the user to press the rear end portion 312 of the coating liquid storage portion 31 (preferably the rear end surface of the coating liquid storage portion 31) with a thumb or the like, which in turn makes it easier to move the coating liquid storage portion 31 toward the tip side.

[0030] The writing instrument 1 further includes a valve mechanism 5 provided at the tip portion 311 of the application liquid storage portion 31, and a pressing member 6 serving as an operating member 6 that opens the valve mechanism 5 by pressing the valve mechanism 5. The pressing member 6 in this embodiment is fixed to the tip portion 321 of the cylindrical portion 32. The pressing member 6 is also directly fixed to the cylindrical portion 32.

[0031] The writing instrument 1 is configured to be capable of assuming a closed state in which the valve mechanism 5 is closed by the pressing member 6 not pressing the valve mechanism 5 to open it, and an open state in which the application liquid storage section 31 moves toward the tip side, causing the pressing member 6 to press the valve mechanism 5 and thereby opening the valve mechanism 5. This also enables the valve mechanism 5 to move axially relative to the pressing member 6. Note that in the closed state, the portion of the pressing member 6 that presses the valve mechanism 5 (specifically, the protruding portion 63 described below) may be in contact with the valve mechanism 5 or may be separated from the valve mechanism 5. In other words, a play portion that provides play between the valve mechanism 5 and the portion of the pressing member 6 that presses the valve mechanism 5 may be provided, or such a play portion may not be provided.

[0032] The writing instrument 1 also includes a cylindrical elastic member 7 that connects the valve mechanism 5 and the pressing member 6.

[0033] As shown in Figures 3 and 4, the valve mechanism 5 of this embodiment has a valve body 51 having a flow path 511 formed therein extending along the axial direction, a valve element 52 that is movable along the axial direction within the flow path 511, a valve seat portion 53 against which the valve element 52 abuts so as to block the flow path 511, and a spring member 54 that biases the valve element 52 toward the valve seat portion 53.

[0034] The valve body 51 is formed into a cylindrical shape extending along the axial direction so as to be capable of housing the valve element 52 and the valve seat portion 53 therein. The valve body 51 also has an annular locking portion 512 that prevents the entire valve body 51 from entering the interior of the application liquid storage portion 31. The valve body 51 also has an insertion portion 513 that is formed to extend from the locking portion 512 toward the rear end side and is disposed inside the application liquid storage portion 31.

[0035] The outer diameter of the engaging portion 512 is formed to be larger than the inner diameter of the tip portion 311 of the application liquid reservoir 31 .

[0036] The locking portion 512 in this embodiment also functions as a first elastic member connection portion 512 that connects the rear end 72 of the tubular elastic member 7. The outer diameter of the locking portion 512 is formed to be smaller than the outer diameter of the tip portion 311 of the coating liquid storage portion 31. This results in a state in which the connection portion between the locking portion 512 and the coating liquid storage portion 31 gradually widens from the locking portion 512 toward the tip portion 311 of the coating liquid storage portion 31.

[0037] The insertion portion 513 has a first extending portion 513a formed so as to extend from the locking portion 512 toward the rear end and so as to contact the inner circumferential surface of the application liquid storage portion 31 over the circumferential direction. The insertion portion 513 also has a second extending portion 513b formed so as to extend further toward the rear end from the first extending portion 513a and so as to taper toward the rear end. The second extending portion 513b is disposed so that its outer circumferential surface does not contact the inner circumferential surface of the application liquid storage portion 31.

[0038] The valve body 52 has an abutment portion 521 that abuts against the valve seat portion 53, a first valve stem portion 522 that extends from the abutment portion 521 toward the tip side, and a second valve stem portion 523 that extends from the abutment portion 521 toward the rear end side.

[0039] The contact portion 521 is disposed so as to contact the valve seat portion 53 from the rear end side toward the tip side. The contact portion 521 is formed in a truncated cone shape tapering from the rear end side toward the tip side, and has a contact surface 521a that contacts the valve seat portion 53 in the radial direction.

[0040] The first valve stem portion 522 is formed such that the tip portion 522a protrudes from the valve body 51 when the abutment portion 521 is in contact with the valve seat portion 53. The first valve stem portion 522 is formed in a cylindrical shape.

[0041] The second valve stem portion 523 is formed such that the rear end portion 523a protrudes from the valve body 51 when the abutment portion 521 is separated from the valve seat portion 53 toward the rear end side. The second valve stem portion 523 can separate the mixing member 314, which can block the flow path 511 of the valve body 51 from the rear end side, from the valve body 51.

[0042] The valve seat portion 53 has a contact portion 531 that comes into contact with the valve body 52. ​​The contact portion 531 has a contact surface 531a having a shape corresponding to the contact surface 521a of the valve body 52. ​​In other words, the contact portion 531 is formed so as to penetrate in the axial direction, and is formed so that the inner diameter increases from the tip side toward the rear end side.

[0043] The contact portion 531 has an annular shaft seal member 531c that contacts the contact surface 521a in the radial direction.

[0044] The spring member 54 has a front end that abuts against the valve body 52 and a rear end that abuts against the insertion portion 513 of the valve main body 51. The spring member 54 arranged in this manner assumes a contracted state in which it contracts along the axial direction as the coating liquid storage section 31 moves toward the front end. Specifically, the spring member 54 assumes a contracted state in which it contracts under the pressure of the valve body 52 moving toward the rear end as the valve body 52 is pressed by the pressing member 6 as the coating liquid storage section 31 moves toward the front end. Furthermore, as the valve body 52 is released from the pressure of the pressing member 6 as the coating liquid storage section 31 moves toward the rear end, the spring member 54 assumes an extended state in which it urges the valve body 52 toward the front end so that the valve body 52 abuts against the valve seat portion 53.

[0045] More specifically, the spring member 54 in this embodiment is a coil spring.

[0046] As shown in Figures 5 and 6, the pressing member 6 of this embodiment has a cylindrical locking portion 61 that prevents the entire pressing member 6 from entering the interior of the cylindrical portion 32, a cylindrical second elastic member connecting portion 62 that is formed to extend from the locking portion 61 toward the rear end and connects to the tip portion 71 of the cylindrical elastic member 7, a rod-shaped protruding portion 63 that is formed to protrude toward the rear end further than the second elastic member connecting portion 62 and directly presses the valve mechanism 5, and a support portion 64 that supports the protruding portion 63 on the locking portion 61 or the second elastic member connecting portion 62.

[0047] The pressing member 6 is disposed so that the locking portion 61 abuts against the tip portion 321 of the cylindrical portion 32 .

[0048] The outer diameter of the second elastic member connecting portion 62 is formed to be smaller than the inner diameter of the tip portion 321 of the tubular portion 32. As a result, a gap G2 in which the tubular elastic member 7 is disposed can be formed between the outer circumferential surface of the second elastic member connecting portion 62 and the inner circumferential surface of the tip portion 321 of the tubular portion 32, as shown in FIG.

[0049] The protrusion 63 is formed so as to be insertable into the first valve stem portion 522 of the valve body 52. ​​As a result, the protrusion 63 abuts against the valve seat portion 53 while being guided by the first valve stem portion 522. The protrusion 63 in this embodiment is disposed inside the first valve stem portion 522 in both the closed state and the open state of the valve mechanism 5. Note that the protrusion 63 may be disposed outside the first valve stem portion 522 in the closed state of the valve mechanism 5.

[0050] The support portion 64 has one or more support pieces 641 formed to extend from the base end 631 of the protruding portion 63 to the inner circumferential surface of the locking portion 61 or the second elastic member connecting portion 62. The support portion 64 is also formed to have an ink flow path 642. The support portion 64 of this embodiment is formed in a cross shape having four support pieces 641 extending in all four radial directions from the base end 631 of the protruding portion 63. Four flow paths 642 are formed between each of the support pieces 641.

[0051] 1, 2, 7, and 8, the cylindrical elastic member 7 connects the valve mechanism 5 and the pressing member 6 such that a front end 71 covers the second elastic member connecting portion 62 of the pressing member 6, and a rear end 72 covers the first elastic member connecting portion 512 serving as the locking portion 512 of the valve mechanism 5. The cylindrical elastic member 7 has a flow path 73 that moves ink flowing out of the valve mechanism 5 from the valve mechanism 5 to the pressing member 6 when the valve mechanism 5 is opened.

[0052] In this embodiment, the rear end 72 of the cylindrical elastic member 7 extends beyond the first elastic member connection portion 512 of the valve mechanism 5 and covers up to a portion of the tip end 311 of the coating liquid storage portion 31. In other words, the cylindrical elastic member 7 reinforces the fixation of the valve mechanism 5 to the coating liquid storage portion 31. It also covers the connection portion between the valve mechanism 5 and the coating liquid storage portion 31, preventing leakage of the coating liquid.

[0053] As shown in Figs. 9 and 10, the cylindrical elastic member 7 connecting the valve mechanism 5 and the pressing member 6 forms an expandable portion 74 between a front end portion 71 and a rear end portion 72, which is expandable in the axial direction. As shown in Fig. 10, the cylindrical elastic member 7 assumes a contracted state along the axial direction as the application liquid storage portion 31 moves toward the front end side. Specifically, as the application liquid storage portion 31 moves toward the front end side and the valve mechanism 5 approaches the pressing member 6, the cylindrical elastic member 7 receives pressing forces in the axial direction from both the valve mechanism 5 and the pressing member 6, which causes the expandable portion 74 to assume a contracted state along the axial direction. Also, as shown in Fig. 9, as the application liquid storage portion 31 moves toward the rear end side and the valve mechanism 5 moves away from the pressing member 6, the cylindrical elastic member 7 receives tensile forces in the axial direction from both the valve mechanism 5 and the pressing member 6, which causes the expandable portion 74 to assume a state extended (from a contracted state) along the axial direction (Fig. 9).

[0054] 10, the cylindrical elastic member 7 of this embodiment is configured so that the stretchable portion 74 can be in a state where it is contracted, contracted, or bent inwardly in the radial direction. Note that the cylindrical elastic member 7 may be configured so that the stretchable portion 74 can be in a state where it is contracted, contracted, and expanded in the radial direction outward.

[0055] Further, the cylindrical elastic member 7 of this embodiment is configured so that, when the stretchable portion 74 is stretched, the inner peripheral surface of the stretchable portion 74 has a cylindrical shape that is substantially straight along the axial direction.

[0056] The material constituting the cylindrical elastic member 7 may be, for example, a thermoplastic elastomer material.

[0057] According to the writing instrument 1 of the present embodiment as described above, the cylindrical elastic member 7 that connects the valve mechanism 5 and the pressing member 6 is provided, so that leakage of ink from between them can be prevented. In addition, by pressing the application liquid storage section 31 toward the tip side, the expandable section 74 of the cylindrical elastic member 7 is contracted, so that the application liquid storage section 31 can move toward the pressing member 6 together with the valve mechanism 5 by the length of the contracted expandable section 74. Then, the protruding section 63 of the pressing member 6 presses the abutment section 521 of the valve mechanism 5, and the valve mechanism 5 is opened. Accordingly, the ink discharged from the application liquid storage section 31 moves toward the tip side via the flow path 511 of the valve mechanism 5, the flow path 73 of the cylindrical elastic member 7, and the flow path 642 of the pressing member 6, and is supplied to the pen tip section 2.

[0058] Furthermore, according to the writing instrument 1 of this embodiment, when the coating liquid storage section 31 is not pressed, the valve mechanism 5 is in a closed state, so that even when a coating liquid with low viscosity or surface tension is used, there is no risk of the coating liquid flowing out to the pen tip, and it is possible to accurately control the amount of coating liquid supplied according to the user's intention.

[0059] Furthermore, according to the writing instrument 1 of the present embodiment, leakage of ink is prevented, so ink stains are unlikely to occur, allowing the user to use the instrument with peace of mind.

[0060] Furthermore, according to the writing instrument 1 of this embodiment, the connection portion between the first elastic member connecting portion 512, which is the engagement portion 512, and the application liquid storage portion 31 is in a state in which it gradually widens from the first elastic member connecting portion 512 toward the tip portion 311 of the application liquid storage portion 31, making it easy to attach the tubular elastic member 7 from the first elastic member connecting portion 512 to the tip portion 311.

[0061] Furthermore, according to the writing instrument 1 of the present embodiment, the cylindrical elastic member 7 covers from the first elastic member connection portion 512 to the tip portion 311 of the application liquid storage portion 31, thereby preventing ink leakage from a gap that may be formed between the valve mechanism 5 and the application liquid storage portion 31. Additionally, the valve mechanism 5 is prevented from accidentally coming off the application liquid storage portion 31.

[0062] Furthermore, according to the writing instrument 1 of this embodiment, the expandable portion 74 of the cylindrical elastic member 7 is configured so that the inner peripheral surface in the contracted state is substantially straight along the axial direction, so that ink can easily flow from the cylindrical elastic member 7 to the pressing member 6. This makes it difficult for ink to remain inside the cylindrical elastic member 7, and can suppress adhesion of ink to the inner peripheral surface of the cylindrical elastic member 7. Therefore, it is possible to maintain a smooth supply of ink to the pen tip portion 2 for a long period of time. This is preferable when the writing instrument 1 is one that can be refilled with ink.

[0063] Furthermore, according to the writing instrument 1 of this embodiment, since the pressing member 6 is directly fixed to the tube portion 32, when the pen tip portion 2 is removed from the tube portion 32, the pressing member 6 is exposed at the tip side of the tube portion 32. When the rear end portion of the application liquid storage portion 31 is pressed in this state, the valve mechanism 5 is opened by the pressing member 6 fixed to the tube portion 32. This allows the application liquid storage portion 31 to be refilled with ink via (the flow path 642 of) the pressing member 6. Even during this ink refilling, since the pressing member 6 and the valve mechanism 5 are connected by the cylindrical elastic member 7, there is no risk of ink leaking.

[0064] Incidentally, the writing instrument according to the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the spirit and scope of the present invention.

[0065] For example, in the above embodiment, a writing instrument filled with ink as the application liquid is exemplified, but the present invention is not limited to this, and the writing instrument of the present invention may be filled with water, India ink, or the like as the application liquid.

[0066] In addition, in the above embodiment, an example was given of a configuration in which the valve mechanism 5 is capable of moving axially relative to the pressing member 6, but this is not limited to this, and the pressing member 6 may be capable of moving axially relative to the valve mechanism 5.

[0067] Moreover, the pressing member 6 may be indirectly fixed to the tube portion 32, thereby being fixed to the tube portion 32. In other words, the pressing member 6 may be indirectly fixed to the tube portion 32 by being fixed to a member other than the tube portion 32. For example, the pressing member 6 may be fixed inside the hollow portion 23 of the pen tip portion 2.

[0068] Furthermore, the cylindrical elastic member 7 may be formed in a bellows shape, which makes it easier for the expandable portion 74 to expand and contract in the axial direction. [Explanation of symbols]

[0069] 1...writing implement, 2...pen tip portion, 21...applying portion, 211:tip portion, 212:rear end portion, 213:expanded portion, 22...holding portion, 221...through hole, 222...rear end portion, 23...hollow portion, 3...shaft portion, 31...application liquid storage portion, 311...tip portion, 312...rear end portion, 314...mixing member, 32...tubular portion, 321...tip portion, 322...rear end portion, 4...sealing member, 41...opening, 5...valve mechanism, 51...valve body, 511...flow path, 512...locking portion (first elastic member connection portion), 513...insertion portion, 513a...first extension portion, 513b...second extension portion, 513c:elastic member fixing portion, 52...valve body , 521...contact portion, 521a...contact surface, 521b...elastic member fixing portion, 522...first valve stem portion, 522a...tip portion, 523...second valve stem portion, 523a...rear end portion, 53...valve seat portion, 531...contacted portion, 531a...contacted surface, 531c: shaft seal member, 54...spring member, 6...operation member (pressing member), 61...locking portion, 62:second elastic member connecting portion, 63...projection portion, 631...base end, 64...support portion, 641...support piece, 642...flow path, 7...cylindrical elastic member, 71...tip portion, 72...rear end portion, 73...flow path, 74...expandable portion, S...internal space, G1...gap, G2...gap

Claims

1. A pen tip portion for applying the coating liquid; a coating liquid storage section for storing a coating liquid; a cylindrical portion formed in a cylindrical shape so as to cover the coating liquid storage portion and fixed to the pen tip portion; a valve mechanism provided at a tip of the coating liquid storage section; and an operating member fixed to the pen tip portion, the operating member being capable of opening the valve mechanism and allowing the coating liquid flowing out of the coating liquid reservoir portion to flow toward the pen tip side via the valve mechanism; a cylindrical elastic member that is expandable and contractable in an axial direction, the cylindrical elastic member connecting the valve mechanism and the operating member and defining a flow path for the coating liquid between the valve mechanism and the operating member; Equipped with the application liquid storage section is movable in an axial direction relative to the pen tip section, The operating member opens the valve mechanism in response to relative movement of the application liquid reservoir with respect to the pen tip portion.

2. The writing instrument according to claim 1 , wherein the operating member presses the valve mechanism to open the valve mechanism.

3. 3. The writing implement according to claim 1, wherein the cylindrical elastic member covers the valve mechanism and the tip of the application liquid reservoir.

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